function clocker(){
    now = new Date();
    end = new Date(document.getElementById('endtime').innerHTML);
	timeEnd = (end.getTime() - now.getTime());
	if(timeEnd>0){
		msPerHour = 3600000;
		par = timeEnd/msPerHour;
		hEnd = Math.floor(timeEnd/msPerHour);
		mEnd = Math.floor((par - hEnd)*60);
		sEnd = Math.floor((((par - hEnd)*60) - mEnd)*60);
		if(hEnd.toString().length<=1)
			hEnd = "0"+hEnd;
		if(mEnd.toString().length <= 1)
			mEnd = "0"+mEnd;
		if(sEnd.toString().length <= 1)
			sEnd = "0"+sEnd;	
		document.getElementById('timer').innerHTML = hEnd + ':' + mEnd + ':' + sEnd;
		timerID = setTimeout("clocker()",1000);
		timerRunning = true;
	} else {
		document.getElementById('timer').innerHTML = '';
	}
}

function startclock () {
	var timerID = null;
	var timerRunning = false;
	clocker();
}